Question

What must each length be in order for quadrilateral JKLM to be a parallelogram?

6. JK=?
7. JL=?

Answer 1

JK = 10 , JL = 14

Explanation:

• opposite sides of a parallelogram are congruent

(6)

JK = ML , that is

3x - 2 = x + 6 ( subtract x from both sides )

2x - 2 = 6 ( add 2 to both sides )

2x = 8 ( divide both sides by 2 )

x = 4

Then

JK = 3x - 2 = 3(4) - 2 = 12 - 2 = 10

• the diagonals of a parallelogram bisect each other

(7)

JL = 2 × JA = 2(2x - 1) = 4x - 2 ( substitute x = 4 )

JL = 4x - 2 = 4(4) - 2 = 16 - 2 = 14